Page 13 - The value of total hip and knee arthroplasties for patients

Osteoarthritis (OA) is a common joint condition, resulting in pain and stiffness, and 1 having a substantial impact on functioning and quality of life of individuals. Hip, knee
and hand OA are the most common forms of OA. Hip and knee OA constitute the
most prevalent causes of global disability, with considerable societal consequences
in terms of associated use of health care resources and costs related to productivity losses.1
Total hip and total knee arthroplasties (THA and TKA) are effective surgical treatments for end-stage hip or knee OA, leading to satisfactory improvement of pain, function and quality of life within a period of 1 year in 80-90% of the patients. The expression of the beneficial effects of surgery in terms of such patient reported outcomes (PROMs) is in line with the focus in health care being more and more on its outcomes in terms of value for patients. Thereby, a shift towards outcome measurements addressing what is most relevant for patients is taking place.2 According to the three-tiered value-based health care model of Michael Porter, apart from health status achieved or retained (Tier 1) and sustainability of health (Tier 3), the process of recovery (Tier 2) is of utmost importance (Table 1).2 This includes the time to recovery and time to return to normal activities, and disutilities of care or the treatment process.
The focus of this thesis is on particularly these aspects, as for THA and TKA, apart from knowledge on outcomes in terms of pain and function, insight into the process of recovery is limited.
This general introduction aims to give an overview of the pathophysiology and epidemiology of hip and knee OA and their treatment, in par ticular THA and TKA, and addresses current gaps in knowledge on the process of recovery.
Pathophysiology and epidemiology
OA is characterised by a slow and intermittently progressive loss of cartilage from the joints. In addition, there may be changes to the subchondral bone and proliferation of the bone at the margins of the joint (osteophyte formation). In addition, the synovial membrane can be periodically irritated, inducing inflammation of the joint.3
General introduction
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